Telephone.



No. 630,797. Fate nted Aug. 8,1899. H. F. BLACKWELL, .IR. & M. A/BLACKWELL.

' TELEPHONE.

(Application filed Dec. 24, 1898.) (No Model.) 2 SheetsSneet l.

THE mums PKTER$ co, PHOTD-LITNQ. vasumomu, u c

No. 630,797. Pateh ted Aug. 8, I899.

H. F. BLACKWELL, JR. & M. A. BLACKWELL. TELEPHONE.

(Application filed Dec. 24, 1898.) (No Model.) 2 Sheets-Sheet 2.

I i? E A TTORNEYS.

m: mums vzrzas co. Pnaruuma. \mswmomn. u c.

HENRY FIELD BLACK'WELL, JR., AND MAUDE ALICE BLAOIUVELL, OENElV YORK, N. Y.; SAID HENRY FIELD BLAOKWE'LL, Jlt, ASSTGNOR TO SAID MAUDE ALICE BLACKlVELL.

TELEPHONE.

FSPECIFICA'I'ION forming part of Letters Patent No. 630,797, dated August 8, 1899.

Application filed December 24,1898. Serial No. 700,261; (No model.)

To (all whom it may concern: ondary 10. The primar'y of the circuit is con- Be it known that we, HENRY FIELD BLACK- tained entirely in the case of the telephone, WELL, J r., and MAUDE ALICE BLACKWELL, excepting where the wire loops pass out into of the city of New York, borough of Manhatthe receiver through the receiver-core 11. 5 tan, in the county of New York and State of The receiver comprises a casing 12, within I New York, have invented anew and Improved which are the coil 13, the steel core 14, and the Telephone, of which the following is a full, diaphragm 15. The coil 13 and core are surclear, and exact description. rounded by a steel thimble 16, which is in This invention relates to improvements in magnetic connection with the core 14, Con- 1o telephones; and the object is to provide atelenected to the diaphragm end of the receiver phone of small and compact form that may is an earpiece 17, here shown in the form of be readily carried in a persons pocket and a bent tube, and it is designed to haveits end adapted to be attached to a fire-alarm system placed within the ear, so that the operator or circuit without impairing or cutting out will not be disturbed by other sounds on the x 5 the circuit for fire-alarm purposes, and is destreet. 7

signed to facilitate operations of the fire-de- A switch is arranged within the receiver, partment and its officers in the execution of and consists of a spring-arm 18, adapted to be their various duties by supersedin g the expushed into engagement with the contactisting system of telegraphing, code-signals, point 19, and extended outward from the 20 and Morse characters. spring 18 is a push-button 20. The switch of We will describeatelephone embodying our course is located in a primary circuit, and invention and then point out the novel feawhen it is desired to leave the instrument in tures in the appended claims. circuit and not in use by releasing the button Reference is to be had to the accompanying 20 the spring 18 will move to its open posi- 2 5 drawings, forminga part of this specification, tion, so that there can be no waste of the bat in which similar characters of reference inditery. cate corresponding parts in all the figures. Having connection with the secondary cir- Figure 1 is a front elevation of a telephone cuit is a jack-plug 21, consisting of a central embodying our invention and showing the pin surrounded by a sleeve of insulating ma- 30 same as attached to a fire-alarm box. Fig. 2 terial, separating the pin from the outer conis a front elevation of the telephone drawn ducting-sleeve. A socket 22 for receiving on a larger scale than that in Fig. 1. Fig. 8 the jack-plug is arranged within each fireis a longitudinal section of a receiver em alarm box and has two connections, one of ployed, and Fig. 4cisadiagrammatic viewillu'swhich (indicated at 23) has connection with 5 trating the circuits. 7 the main fire-alarm line 24, and the other, 25, The telephone comprises a casing 1, proleads to the ground. These connections are vided with a swinging door2 and having a bail normally open; but when the jack-plug is in- 3, adapted to be engaged over the inner door serted in the socket to place the secondary 4: of a fire-alarm box 5that is, the bail has circuit in the telephone in electrical connec- 40 a hook portion at its top to engage over the tion with the fire-alarm circuit and with the top of the alarm-box door-and as the top of ground through the condenser 8 without placsaid door is curved it is obvious that the teleing a ground on the wire one wire 26 of the phone will not only be suspended, but will be secondary leads to the outer shell of the jackprevented from slippinglaterally. Arranged plug 21 and the other Wire 27 leads to'the 9 5 5 within the casing is the diaphragm 6 for the inner pin of the jack-plug. U

transmitter, and also arranged in the casing In operation when it is desired to telephone is a battery 7, preferably of the dry type, to headquarters or to any other place on the having spring connections or contacts with line the jack-plug is to be inserted in the the primary circuit. Also arranged within socket 22 and the instrument hung upon the I00 5c the casing area condenser 8 and an inductioninner door of the fire-alarm box, as plainly coil comprising the primary 0 and the secindicated in Fig. 1. Then by placing the receiver to the ear and closing the switch the circuit is complete, so that conversation may be had through the telephone.

While We have described the instrument as particularly adapted for the use of the firedepartment, it is to be understood that it will also be useful as an instrument of accuracy in making capacity determination and the other tests for locating faults in underground constructions or overhead Work by being used in place of a galvanometer, as at present.

Having thus fully described our invention, We claim as new and desire to secure by Letters Patent 1. A receiver foratelephone, comprising a casing, a coil in the casing, a diaphragm, a metal core in the coil', a metal thimble surrounding the coil and connecting with the core, and a switch in the receiver for controlling the primary of the instrument, substantially as specified.

2. A receiver for a telephone, comprising a casing, a coil arranged Within the casing, a diaphragm, an ear-tube extending from the diaphragm end of the casing, a steel core in the coil, a steel thimble surrounding the coil and having connection with the core, and a switch in the receiver, consisting of a springcontact and a fixed contact, said contacts be ing in the primary of the instrument, and a spring, substantially as specified.

HENRY FIELD BLACKWELL, JR. MAUDE ALICE BLACKWELL.

NVitnesses:

JAMES M. J ONES, JOSEPH; E. CUFF.

3 push-button extending outward from the V 

